The present invention relates to a system that is configured to measure ground and soil properties through sensors which are located in the vicinity of traction anchors, where these anchors periodically make a firm and static contact with the ground to generate traction for a platform, a ground engaging tool, or a load to be pulled. The sensor data is processed by a computing system and either offered to the user, or used to manage the ground in an semi-autonomous or autonomous manner. The invention is applicable to work that relates to the ground, such as agriculture and forestry, civil engineering, mining, clearing space of obstacles, and geotechnical studies.
The measurement and control of ground properties are extremely important to the management of crop, water and soil. For example, ground properties affect:                The production of biomass, in particular the root growth of crops, the spread of pathogens, the availability of water and nutrients, and crop yield.        Infiltration and storage of water, the filtering and leaching of nutrient, pesticides, and harmuful substances.        Stability and erodibility of soils.        Production, storage and release of gases like CO2 that affect the climate.        Storage and protection of flora and fauna.        Trafficability for vehicles.        Drawbar strength, energy consumption, and lateral deviation of ground engaging implements like tillage implements.        Suitability of ground for construction.        Value for mining of minerals and fuels.        Conservation of fossils and archaeological artifacts.        The motion in the ground of dangerous objects like buried explosive mines.        
The combination of specific ground properties affects, in general, the health status and the quality of soil, and the ability of soil to function as a living ecosystem, to enable civil engineering projects, and to positively influence the climate and the quality of groundwater.
Ground properties referred to by the present invention comprise, preferably but not limited to other properties: slope, the type of material that covers a soil surface, temperature, moisture content, water storage capacity, infiltration rate, texture, structure, cementation, porosity, size of the hard lumps, clay content, type and amount of organic matter, depth and distribution of roots, the presence, state and activity of earthworms, nematodes, ants, termites and other animals, the presence, state and activity of microorganisms, bacteria, fungi and weeds, the content, state and availability of nitrate, phosphate, potassium, iron, boron and other macro and micronutrients, aluminum, lead and other toxins, other minerals, the amount and composition of atmospheric air and other gases, alkalinity, salinity, pH, electrical conductivity, the dielectric permittivity, soil strength, stone content, the dry bulk density, the depth of the topsoil, the vadose zone, the water table, and the presence of distinct horizons or layers that, for example, facilitate or hinder the movement of water and minerals and growth of roots.
Knowledge of ground properties is also useful for the following activities:                Decide the time, location, type and depth of operations such as tillage, planting, irrigation, fertilization or pesticide application, and to select the appropriate tillage tools, such as moldboads, cultivators, discs, chisels, cylinders, harrows, or subsoilers.        Predict soil degradations like erosion, compaction, and contamination, and take measure to prevent them.        Nivellation and terassing.        Find, study, and preserve archaeological sites.        Deciding the location and depth of drainage pipes and other pipes and electric cables, fiberoptic cables and other cable that are laid on the ground or buried in the ground, for example, to allow optimal drainage, to protect them from harm or to minimize environmental interference.        Dig trenches, and stabilize and maintain banks of bodies of water.        Locate valuable minerals.        Find a suitable way for navigation and transport, and avoid or engage obstacles such as rocks or mines.        Manage ecological, geological and climatic systems: depending on ground properties, it can be determined whether certain types of land management will be advantageous or have drawbacks. Land management that leads to carbon sequestration, for example, may be advantageous since it mitigates global warming. Meanwhile, land management which leaches pesticides may be inadvisable, because it contaminates groundwater.        Achieve persistent autonomy for autonomous devices, since the degree of autonomy of an autonomous device depends on the knowledge that is available on the state of its environment. Trafficability for example depends on the firmness of the soil.        Decide on the depth of soil to be removed, how to contain and neutralize contaminants and how to assess the risk of leaching.        
Some ground properties such as clay content tend to be stable over many years and do not need to be measured frequently. Other properties, such as soil water content can change significantly from day to day and frequent measurements may be of economic advantage, for example to control irrigation. Some ground properties like clay content can change dramatically within a meter's distance and call for high resolution measurements, while other properties like pH are stable over dozens of meter and call for measurements of lower resolution.
Measuring ground properties requires time and resources. Measurements such as soil temperature at depth are best taken in-situ and require penetration of the ground by a probe. Some ground sensors must have a good physical contact with the ground and have a non-zero response time. For example, it takes about 10 seconds to obtain a useful reading of an ion selective electrode.
Ground properties are often measured with hand held tools or with a dedicated vehicle that stops regularly in the field to penetrate and probe the ground. Non-stationary work like tillage, earth moving, or transport of cut trees is normally done with diesel tractors, because of their efficiency and robustness. It is impractical to measure ground properties with sensors that need to be stationary during such non-stationary work, since to halt and accelerate a diesel tractor carries a significant cost in time and energy consumption. When stopped, a diesel tractor that plows or drags a load performs no useful work.
During normal operations of a non-stationary tractor all parts of the tractor system move over or through the ground at a relatively high speed, so that it is technically challenging to establish permanent ground contact for any length of time. The company Veris Technologies in the United States is a leader in soil sensing technology and perhaps the only provider of on-the-go chemical soil analysis. One product offered by this company measures chemical soil properties such as pH by extracting soil samples from a moving vehicle, and the samples are analyzed on the vehicle. There is no solution that chemically analyzes a sample of soil in-situ while the vehicle moves and tills the soil or pulls a load.
Variable depth plowing promises to save substantial amounts of energy by plowing only to the depth that is really needed. It depends on the ability to measure soil strenght at different depths. Soil strength can be measured during plowing operations by combining a measurement of speed over the ground with the reading of dynamometers that are connected to the drawbar. But this method does not allow identification of soil strength at different depths. Another method to measure soil strength is to use pressure sensors in the tillage tool itself. However, this greatly complicates the design of the tillage tool, which is generally subject to heavy wear, and can interfere with the tillage operation.
The present invention aims to solve the above technical problems, which characterize the devices and methods that form the state of the art.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.